Surface and Groundwater interaction in the Great Miami Valley Watershed: Isotope Geochemical Approach
Groundwater-surface water interaction play a vital role in determining the quality and quantity of groundwater as well as sustainable water resources management. Surface water and groundwater are key components in the water cycle that variably interact depending on geology, topography, and rainfall seasonality. We use environmental isotopes of Hydrogen (δD) and Oxygen (δ18O), which are conservative dual tracers, to provide key information on the movement and flux of water in the hydrologic cycle, degree of mixing between reservoirs, and spatial and seasonal variation of surface and groundwater interaction. Here we examine the degree of surface and groundwater interaction in the Great Miami Valley Watershed (GMVW). Weekly precipitation samples from Dayton, OH, spring and fall groundwater samples from the Great Miami Buried Aquifer and weekly river water samples from four locations (Still Water River, Mad River, and two locations on the Great Miami River) were collected and analyzed for δD and δ18O. Our initial data set shows that the average isotopic composition of the rivers is -6.71±0.19 ‰ for δ18O and -42.63±1.11‰ for δD during the warm season and -7.42±0.12‰ for δ18O and -47.69±0.88‰ for δD during the cool season.The average isotopic composition for groundwater is -7.16±0.49 ‰ for δ18O and -45.29±2.73‰ for δD during the spring and -7.05±0.50‰ for δ18O and -44.72±2.83‰ for δD during the fall. Our result based on an isotope two-component mixing model shows high degree of connectivity between surface and groundwater in the Miami Valley. Locally, rivers and the Great Miami Buried Aquifer shows more than 75% mixing. The outcome of this study will provide useful information on available seasonal groundwater recharge and aid in future water resource management.
Zelalem K. Bedaso
Primary Advisor's Department
Stander Symposium project
"Surface and Groundwater interaction in the Great Miami Valley Watershed: Isotope Geochemical Approach" (2019). Stander Symposium Projects. 1500.